Hacking SXOS won’t boot CFW anymore, OFW boots and works fine (console with SX Core chip)

[st_los]

I didn’t mess with CFW/OFW at all. Everything worked just fine. But after powering off my Switch while in CFW (long press Power button – then Power Off) I can’t get CFW working again.

After powering on my console, I’m able to get into SXOS boot menu (pressing Vol+). After selecting "Boot custom FW" all I get is black screen. "Boot original FW" option works fine, I'm able to get OFW working.
When I try to power on my console normally (press Power and wait for turning on), all I get is SX OS splash screen and then black screen.

I’ve tried to replace Emunand folder’s content on the SD Card with the content of my sxos backup folder. It didn’t help.

Here’s what I have:

OFW 10.1.0
Switch Console Type: Mariko
SX Core firmware version: v1.3
SX OS v3.0.4
Emunand enabled
No payloads found on MicroSD card.
Samsung SDXC EVO Plus 256 Gb card (genuine), exFat
Battery is fully charged.

(I didn’t update/install any software (only games via DBI MTP Responder). Neither OFW nor CFW since I’ve bought my Switch last September).

Please, tell me what can be done in this situation? Should I try “Repair GPT”, "Reflash v.1.3" or other options? I’m afraid to get my console bricked, thus I’ll wait for your advice.

 

[wiiNinja]

I don't have SXCore; I do have SX Pro (dongle) in an unpatched Switch- just giving you suggestions. The problem could be the mod chip, or the SD card. You'll need to eliminate the SD card as a culprit. Somethings to try: check the SD card for errors, try to create a new emuNAND using a different card. That will tell you if the problem is with the mod chip. If it is the modchip, that's a hardware problem, and that's much harder to solve. You may have to get someone with the skills to diagnose and fix (cold solder joints? bad chip?)
Edit: Or just as a test, try to get Atmosphere to work.

 

[st_los]

Thanks for advice! The SD card was faulty indeed. Guilty as charged. Maybe not the card itself, but filesystem.

1) I’ve copied all the content from SD card to PC (took half and 3 hours for 256 GB).

2) I’ve formatted SD card from exFAT into FAT32 format using FAT32Format

3) I’ve put back all the files back on the SD card (another half and 3 hours)

4) The CFW is working fine by now

There is a thread on GBAtemp where people explain why FAT32 is better than exFAT for using with CFW. Now I tend to agree with them.

 

[Litvinkov]

It's probably not about exfat/fat32 (even though yes, fat32 is apparently better), but rather about that sd card. Turns out it's a known issue that the modchip (or the sx os) has problems with samsung cards. I have the same card as you (Samsung EVO Plus 256) and it usually takes 3 or 4 tries/reboots for the cfw emunand to load.

 

[st_los]

It’s a pity, considering there are no other viable options other than Samsung Evo+. Some cards may be of better quality, but their speed is inferior. And the speed is important to run EmuNAND. As for me, I had bad luck with SanDisk SDXC cards, thus I cannot recommend them to anyone (they tend to malfunction without any visible reason).

 

[DPyro]

It’s a pity, considering there are no other viable options other than Samsung Evo+. Some cards may be of better quality, but their speed is inferior. And the speed is important to run EmuNAND. As for me, I had bad luck with SanDisk SDXC cards, thus I cannot recommend them to anyone (they tend to malfunction without any visible reason).

Speed is irrelevant when it's capped on Switch.

 

[Maupiti]

It’s a pity, considering there are no other viable options other than Samsung Evo+. Some cards may be of better quality, but their speed is inferior. And the speed is important to run EmuNAND. As for me, I had bad luck with SanDisk SDXC cards, thus I cannot recommend them to anyone (they tend to malfunction without any visible reason).

Well, being using sandisk sd cards ( 200 and 400 go) for over 4 years, and never had a single issue..,But, they are genuine.

 

[punderino]

It’s a pity, considering there are no other viable options other than Samsung Evo+. Some cards may be of better quality, but their speed is inferior. And the speed is important to run EmuNAND. As for me, I had bad luck with SanDisk SDXC cards, thus I cannot recommend them to anyone (they tend to malfunction without any visible reason).

While that is all true, the Switch can only read UHS-1 so anything faster would only be worth it if it was more reliable than another one.